Paper: CSIR-NET December 2019 · Subject: Inorganic Chemistry · Chapter: Chemical Bonding · Topic: Chemical Bonding – General · Marks: 2 · Difficulty: Medium
Consider the following statements for Allred-Rochow electronegativity ($\chi$AR):
(i) $\chi$AR is directly proportional to $\mathrm{Z_{eff}}$
(ii) $\chi$AR is inversely proportional to $\mathrm{Z_{eff}}$
(iii) $\chi$AR is inversely proportional to r(covalent).
(iv) $\chi$AR is inversely proportional to $\mathrm{r^{2}}$(covalent).
The correct statements are
(a)(i) and (iv)
(b)(ii) and (iv)
(c)(i) and (iii)
(d)(ii) and (iii)
Answer
Answer: A ✓ checked by 4AB · confidence high
Explanation
Allred–Rochow: $\chi_{AR} = 0.359\,Z_{\mathrm{eff}}/r^{2} + 0.744$ (r = covalent radius in Å) — proportional to $Z_{\mathrm{eff}}$ and inversely to r²: statements (i) and (iv) (a).